Controller for electric circuits



July 25, 1933n a s. 5 GREEN 1,929,034

CONTROLLER FCR ELECTRIC CIRCUITS Filed Jan. 26, 1931 2 Sheets-Sheet lJuly 25, 1933. s sl GREEN 1,920,034

CONTROLLER FOR ELECTRIC CIRCUITS Filed Jan. 26, 1951 2 SheelS-SheeI 2`KJ 5A/eem INVENTOR,

A TORNEYl Patented July 25, 1933 f UNITED sT-A 'rss STANLEY s. GREEN,cr-LA FAYETTE, inniANA, AssIGNoR ipo DINC'ANl ImEcTmc MANUFACTURINGCOMPANY, F ILLINOIS f CONTROLLER FOR ELECTRIC CIRCUITSA Application iledJanuary 26, 1931. Serial No; 511,382.

My invention relates Vto controllers forf controller which is inclusiveof a body of electric current conducting material, such as mercury, that1s normally contained 1n the Ybore or passage of a conduit` made of infksulating material. This current conducting liquid serves toelectrically connect two electrodes of the associated circuit, when thedevice is in, circuit closing position. When there is, an abnormal flowof current through the device, theliquid conductor, or a sutlicientportion of it, is expelled to break the electrical connection betweenthe electrodes and thereby open the circuit and guard the translatingdevice-'within the circuit. The liquid conductor and associatedelectrodes land partsthus constitute a circuit-protecting switch: f I Vj My present inventionhas for its general objects the yformation of aswitch structure which is simple V'and yet Strongenough to withstand theviolence which attends its operation, the provision of a greatresistance to'flash-over within theswi'tch to minimize destructivearcing, provision of ay sim ple and rugged support for thecircuit-controlling element within a housing enclosing the structure,the attainmentJ of a construction and relation of parts which will lendi -themselves to easy and economicalquantity production, and theprovision 'of a method of connectingthe switch to the cir- Vcuit bysupporting means inclusive of sliding or rubbing contacts to allow thedesired movement of the switch betweenffkon and off positions.w Afurther object is to make the circuit controller and its .supportingmeans so that one or more of them can be readily mounted in the common-type of metal switch box or assembled in the usual distributionpanelboard enclosure. An additional object is to provide a simple on7and 01T indicator for the circuit controller.

which In carrying out my invention, I reenforce the conduit ofinsulating material with a metallic shell and clamp it firmly 'in spacedinterior relation 'to the\container.` I desirlably provide suchcontainer in the form of two mating shells or cups of insulatingmaterial clamped together-with a sealing material therebetweenandarranged to be imperforate to the outer air. The reenforcing andsupporting shell on the conduit of insulating material desirably has arelative shape and spacing and is so insulated with respect to theelectrodes and liquid conductor injthe conduit therebetween as toprovide a relativel great flash-over resistance for the control edcurrentfaround the conduit and through the reenforcing shell or supportthereof. `Slidable mounting means is provided for the housing enclosingtheA circuit controller which not only rotatably supports the same, butprovides lead-in and lead-out connections for the controlled current insuch a way that such current cannot be interrupted except within theswitch housing. A base for the housing and slidable mounting .means is'provided which adapts the entire assembly for inclusion in a metal boxor for use as a unit in a dis- .tributionpanelboard On the front of theciicuit-controller housing is mounted a counter-weighted disc having-awindow therein. This disc isl rotatable and occupies different relativepositions with respect to the housing as the. housing is rotated. Thusthe words on and oH can be read through the disc window .when thehousing occupies such respective positions.

Thexinvention has other characteristics that will be more fullyexplained in connection with the accompanyingvdrawings, in

Figure-i1 is a front elevation of the circuit LA FAYETTE, y INDIANA1 ACORPORATION. 0F

controller, exclusive of its mounting and base, in the normal onposition;

y VFigureQ, a fragmentary side elevation of the circuit contrcpller in aposition intermediate between the on and an off position, part of thesupporting'base being ,in section; Y 3

Figure 3, a 'front elevation, partially in *sec-tion, ofA the circuit.controller casing in" theI on position, the front section of such casinbeing omitted for the purpose 'of Jshowing interior parts;

Figure 4, a view, somewhat similar tol Figure 3, but showing thecontrollercasing -in its oi' position and illustratin `nected incircuit;and

Figure 9, a perspective view of one of the circuit controllers ymountedin a cabinet. In the forms of the invention illustrated, 'the casing ismoulded of insulating material and is inclusive of the front half orremovable cup-shaped section or shell.y 1 and thel rear halfy orremovable cup-shapedsection or shell 2.v These casing sectlonsf areclamped snugly together as by means of the metallic bolts 3 which 'passthrough exten' nal ears 3 formed on the casing section.

i' The pressure exerted by said bolts is suliicient to bring theengaging fiat faces Vof the casing. sections into intimate contact sothat the casing is imperforate in this reg-ion and throughout the entirecircumference ofthe casing which is desirably cylindrical. A film oflcem'ent such as bakelite varnish, yis desirably applied to these Hatsurfaces be;

v fore placing them together and tightening bolts 3. The circuitcontrolling element is Within the casing and isloperableto on andoPpositions by suitably moving the casing. This circuit controllinelement includes as shovvn in the embodlment ofthe inventionillustrated, a control tube 4, preferably of porcelain produced by thewet process." This tube is surrounded by a reenforcing metal jacket 5that is preferably bf iron and is initially of smaller internal size'than the ,iportion of the y conduit it surrounds: Jacket 5 ispreferably formed from i sheet metal as by drawing and then pressedinto" position over tube 4.v

A feed tube 6, preferably of metal, communicates with one end of thebore of tube 4. At' the end adjacent'tube 4, None end of this feed tubeis fastened, as by threads to' va flange 7. Flange 7 is electricallyinsulated from jacket 5 by means of insulating washers 8, 9 and 10,preferably formed of a heatV resisting insulation such as lasbestospaper or asbestos pressboard. Such insulat` heat resisting com'oundor'binder, such as bakelite varnish, i desired. Flange 7 and itsinsulating washers 8, 9 and 10 are positioned in the bottom vof jacket 5and tube 4 is forced into the ,jacket.- At itsendadjacent nthe tube 6,the jacket 5=has a rim 5. When tube 4 is forced into the jacket, flange7 together withits insulating Washers isl through the strongnon-shatterable metal feed tube 6, andconduit 4 is Valso strengthenedand made'non-shatterable by the metal reenforcement of jacket 5, the rim5 of jacket 5, flange 7 and fingers 52." Itrwill be although thecontrolling element the feed' tube andprocelain conduit is substantiallymetal-clad throughout, feed tube 6' is completely insulated electricallyfrom ,jacket 5 and thereby ,preventslash-.over of 'the controlledcurrent along a path outside of porcelain tube 4 and inclusive of metall jacket 5. If desired, an insulating varnish or paint can be' appliedto the outside of feed tube 6, the exposed end portion of flange 7andthe outside of jacket 5 to make this insulating constructionstill-more eil'ective, although such additional precaution ,is notessential.

On the outside of jacketw is fastened securely, as by spot-welding, atransverse metal support piece 11. The ends of this piece nest snuglyinto recesses 11'? and 112 provided therefor in the respective front andrear casing halves. This support positions the current-controlling unitcomprising tube 4securely and accurately. in the housing independent ofany other means for support. The heat and arcing attendant to operationare localized Within tube 4 and spaced a substantial distance from thewalls of the con-` tainer by this construction? The end of the bore ofthe conduit 4 remote from the tube 6 is enlarged to form a vvell 12adapted to receive the tip 13 of a metallic electrode 13 whichcontactswith the mercury 14, or other liquid conductor conapparent fromthis novel construction that including.

tained in the conduit bore, and the ivell en- Y largement 12 when thedevice is in circuit closing position. Slight clearance desirablyIintervenes between the wall of'well 12 and v the electrode part 13'..Electrode 13 is fastened in position upon a metallic lead-in stud 15 by'a screw 15 threading into the ing a part of casing section 2 is securelymoulded about the knurled end of lstud 15 which passes through to theexterior of the e5 ing washers may be impregnated with af casing. rlihecurved end 13 of the metallic l inner end of this stud.' A bess 16constitut? electrode 13 has suliiciently full Contact with the liquidconductor in the well 12 Without substantially obstructing the freepassage of vthe liquid conductor and gas rapidly escaping from theconduit bore upon severe short circuit. A portion of thel electrode 13is formed to constitute a barrier 132 toprotect the casing Wall from theexplosive effects of the hot mercury or liquid conductor and the vaporthereof that are ejected wviolently from the conduit bore uponshortcircuit. This liquid conductor vapor and the attendant arc of hightemperature might otherwise strike the casing wallforcibly withinjurious effect. Said shield or barrier 132 also absorbs much of theheat contained in the 1 liquid conductor and vapor striking it sincebeing a metal it has a -relat'ivelylargeheat ab-' sorbing capacity thatacts to condense the liquid conductor vapor and' has a marked effect inquenching any arc which might arise between the electrode 134 and otherparts of opposite electrical polarityf in the casing. A small extension133 "on electrode 13 is shaped to touch the casing and thus position itand'preventthe entire electrode 13 from tending to turn aboutv screw 15"upon explosive impact of mercury vapor against it on short circuit..Electrode 13 isr preferably made of copper or other metal of highelectrical and thermal conductivity but plated with a mercury-resistingsub-l stance such as iron or nickel. The other metals exposed in thecontainer to the action of mercury or mercury vapor may also be made outof non-ferrous metal such as copper, if that metal is coated with iron0r other mercury resistant vmetal.

Mating projections 17 and 18are respectively integrally moulded with thecasing sections 1 and 2, and yform with contiguous portionscf the casinga funnel-shaped space 19. The receiving end of the feed tube 6 farthestfrom conduit 4 may be freely received Within the stem of the funnel tovirtually constitute a continuation thereof. A' considerable degree ofclearance between the stem of feed tube 6 and the lower end or stem offunnel 19 is, however? desirable in order to provide a tolerance whichin manufacture will insure both halves of the casing going togetherWithout being pre- `vented by the end of feed tube 6 in the stem of thefunnel 19. I have found a clearance on all sides of the feed tube ofapproximately .010 satisfactory for this purpose giving a diameter offunnel stem approximately .020 greater than the diameter 0ffeed tube 6.f

Another electrode 20\is providedi to dip into the liquid conductor inthe feed tube and thus make 'electrical connection through the liquidconductor in the feed tube and/ the bore of conduit` 4 with theelectrode 13.

Such yelectrode 20 is conveniently punched` from sheet metal and issupported uponan- 4other lead-in stud 2l by means of a screw 21-threading into the interior end of this stud. Lead-in stud .21 isknurled and is cast into "and passes through the casing half 2 in thesame manner as its companion lead-v in stud 15 and has around it a boss22. Electrode 20'passes through a small slot 23 in the interior portionof the wall of the funnel space -19 and has a'tip 20 which dips asubstantial distance into and below the level of the liquid conductorinfeed tube 6 when the liquid conductr is at a normal level in such tubein the normal on position of the device as shown in Fig. 3. The bore f Ifeed tube 6 is made large enough to admit such electrode tip 20' withlclearance all around it to allow for free passage of the mercuryinto andout of the tube. The tip 20 is provided with a small hole 2()2 passingthrough it transversely through which a small steel pin may be passedand anchored into the side walls of fed tube 6 after electrode tip 20 isinserted in place therein.

This is for the purpose of preventing electrode 20 from'being blown outof thefeed tube 6 by the violent passage of mercury therethrough' uponsevere short-circuit conditions.

Conduit 4 and feed tube 6 are so positioned with respect to the casingthat when the device is turned from on to off position, the mercury willbe discharged therefrom into the surrounding space and open the circuit,the liquid conductor falling to vthe 'then bottom of the casing as(indicated at 14'in Fig. 4. When the device is turned from uoff to onposition, 'the cup of funnel 19 Will. gather mostof the liquid conductorat 14, this gathered liquid pass- N ing by gravity through the cup andstem of the funnel into the feed tube 6, and thence to thelbore ofconduit 4 and well 12, whereby the circuit ^is closed. ln the event theliquid conductor vaporizes while the controller is on with resultinginterruption vof the cirw cuit, it is only necessary to operate thecontrollersuccessively to offl and on positions when the liquidconductor will be returned to the tube 6 and conduit4 and the f circuitreestablished without the renewal of any parts. To insure closure of thecircuit, I provide an excess of mercury or liquid conductol; which findsAlodgment in the then i bottom; of the 'casing as indicated at 14 inFig. 3, this exce flowing from the Well 12 when thedevice has been fullybrought to its on or circuit closing position. When the device is in theon osition andthe v control circuit is closed at a lamp orl othertranslating device, the circuit is inclusive of lead-in, stud 21,electrode 20, vand electrode tip 20', the mercury in the bore of feedtube 6, A'the mercury in the bore of conduit 4 and 130 50 is' rotated,the disc 34 is free to assume a well enlargement 12, electrode 13',elecl trode 13 and thence to lead-in stud 15.

A mounting device not only supports the.

housing but provides a path for controlled current into and out of thehousing. Three insulatingmembers, preferably of moulded material, 24,25, and 26, are clamped to-.x getheron a bolt l27 secured at one end-'bynuts 28.- Between these insulating members and 32 which alsol serve/tofasten1 the wires are clamped radial connectors 29 and 30 connecting tostuds 15 and 21. Connecting straps 31 and 32 are also clamped betweensaid insulating members24, 25, and 26. The ends of connecting straps 31and 32 are fastened to an insulating base 33 by screws- 31 Which. maylead to the circuit to be controlled. vThe base 33 maybe recessed as at33 in order to receiye a portion of the -insulating member 26'.

`The casing may be-moved through approximately 180- degrees to its on`and4 off position and in so doing sliding elec-y trical contact ismaintained between radial connector 29. andconnecting strap 31 in' onecase and between radial connector and connecting strap 32 in anothercase.

Stops 312 .and l322 are provided` on connecting straps 31 and 32 toengage corresponding projections such as 29 on. radial connectors 29 and30 to limit therange of radial connector 292v f housing, aproper'dista'nce, allows suitable sliding contactwhile the housing-isbeing 4moved .from one'position to another -and'- also supports thehousing eli'ectiv'ely and simply.

A disc 34 is mounted) on -a p1`n135 on the face of the housing. A window36 lis formed in this disc and' diametrically opposite such window isplaced a-- small counter weight37, such as a lead button. When thecasing position s uch that the lead counter weight l 37 is always at`the bottom. The wordfon? is placed on thecasing in such a position thatit is observable through the windowv of the disc lwhen the Vcontrolleris in 'its on.

^ position.l 'In Figure 1, such word onis Vshown thus visible..Similarly the word off may 'be placed upon the casing in a properpositionJ to be observable through.v

said `window when the controller' hasv been operated tofits oliposition. A bead or v rim 38 is raised in circular formation'aroundthe'periphery of the disc 34 in orderto Vprotect the same from beingdisturbed or re- `resaca-1 moved' inadvertently the casing face.

Name plate data may be printed on the disc 34, if desired.

It is evident that the complete assembly-of base, 'carrierv and circuitcontroller constitutes a complete circuit breaker device capableofswitching the controlled circuit on and olii' and in addition having apredetermined current-car'rying capacity beyond which the circuit isautomatically opened but may bereclosedmanually without the renewal ofany of its parts.. Such a circuit breaker device can be used inmany waysand ifdesiredcan be mounted in the ordinary type ofmetal switchv` boxsoI that all wires,to and from it can bev completely. en-

closed and metal-clad. A particular adap-' tation of the present form ofmountin would be in connection with suchA formso metal-clad switchyhousings as are described in mycopen'ding application No. 463,174 filedJune 23, 1930, wherein a liquidconductor circuit controller somewhatsimilar to the present described controller but with a different form ofmounting is described. in`

use withv a metal box or cabinet to form av meter entrance. s'witch.Asan example of how the present switch and method of mounting can beaplied to applications where a box vorfcabnet is employed, reference is'made to Figure 9 which showsan enclosin boxor housing 40 having a .cover41.

Within this box is mounted the casingvand itsbase. vA hole 41 is cut inthe cover-of the box through which the faceof the casing may extend andbe accessiblefto.

manually andturn t-thefon or olf position. The cover of the box 40 maybe hinged as at 40v and be providedv with a seal assembly 42 bywhichunauthorized ersons may be kept from undetectably havmg access tothe box. A conduit 43 is shown asr ,tened to one side of box 40 throughwhich one or more 'wires for connection to the circ uit controller maypass. f I

The circuit breaker device assembled with an enclosing cabinet as inFig. 9 renders the .circuit breaker manually operable by using the bq'dyof the casing 1, 2, as a handle from the exterior of the cabinet withoutthe necessity of tampering with anythingiwithin the.

cabinet or even ofbpeningthe cover.

I claim: A 1. An electric circuit controller including, an insulatingcasing, liquid conductor carried said casing, a `control unit in saidcasing including a dielectric current limiting control tube having ametallic feed tube as sociated therewith and a ymetallic jacket whichreinforces'said control tube and secures said feed tube thereto, a pairAof electrodes arranged t8 lbe connected by liquid conductor in saidcontrol-unit when the controller is on, the first of said electrodesassociated withsaid' feed. tube and the second of ysaid electrodes beingat the other end lthe influence of excess current, said container beingsubstantially sealed to confine any discharged vapor therewithin whereit contacts with said electrodes and other metallic parts, said metallicjacket being insulated from said metallic feed tube: and from bothelectrodes to minimize the chance of arcing between said jacket and saidsecond electrode.

2. An electric circuit controller including a casing, a tubular conduitin the casing, liquid conductor carried in the conduit when thecontroller is onlan'd discharged therefrom into the casing as thecontroller is operated to off, electrodes adapted to be connected by theliquid conductor in the conduit when the controller is on, said conduitincluding metallic'and dielectric sections, and means joining thesections including a single metallic member carried by the dielectricsection andengaging a surface thereof facing away from said metallicsection, and insulation interposed between said memberl and themetallic. section.

3. An electric circuit controller ofv the volatilizing cut-out typeincluding a casing, a tubular conduit in the casing, a volatilizingliquid conductor carried in the conduit when the controller is on anddischarged therefrom into the casing as the controller is operated tooff, electrodes adapted to be connected by the liquid conductor when thelatter is disposed in the conduit, said conduit including a metallicsection and a dielectric section in which latter volatilization 'ofliquid conductor is initiated by excessive current to open the circuitwhile the controller is on, and means joining the sections including ametallic member and insulation interposed between said member and saidmetallic conduit section, said member also constituting a reenforcingjacket for the dielectric vsection and engaging a surface thereofl'facing away from said metallic section.

4. Anf electric circuit controller of the volatilizing cut-'out typeincluding a casing, a tubular conduit in the casing, a volatilizingliquid conductor carried in the conduit when the controller is on anddischarged therefrom into the casing as the controller is operated tooff, electrodes adapted to be connected by the liquid conductor when thelatter is disposed in the conduit, said conduit including a metallicsection and a di? electric section in which latter vol-atilization o fliquid conductor is initiated by eX- cessive current to yopen thecircuit while the controller is on, and means joining the sections, saidmeans including a metallic reinforcing jacket surrounding the dielectricsection and having one end inturned and spacedY from the adjacent end ofsaid section, an enlarged terminal on the metallic section extendingbetween the inturned end of the jacket and the dielectric section,y andinsulation interposed between said enlarged terminal land all parts ofthe reinforcing jacket.

5. An electric circuit controller including a casing, a strut within andSupported by opposite walls of the casing, a tubular conduit fixed toand supported by said strut, liquid conductor carried by the conduitwhen the controller is on and discharged therefrom and returned theretoas the 'controller is successively operated from on to off and from olfto on, and electrodes adapted to be connected by liquid conductor whenthe latter is disposed in the conduit.

6. An electric cii'cuit controller including a dielectricl casing, ametallic strut within 'and supported by opposite walls ofthe casing, atubular conduit having a metallic outer face welded to said strutwhereby the latter supports the conduit within the casing, liquidconductor carried by the conduit when the controller is on anddischarged therefrom and returned thereto as the controller issuccessively operated from on to off and from off to on, and electrodesadapted to be connected by liquid conductor when the latter is disposedin the conduit.

7. An electric circuit controller including, 100

an insulating casing, liquid conductor carried in said casing, a controlunit in said casing including a dielectric current limiting control tubehaving a metallic feed tube associated therewith and a metallic jacketwhich reinforces said control tube and secures said'feed tube thereto, apair of electrodes arranged to be connected by liquid conductor in saidcontrol unit when the controller is on, the first of said electrodesbeing l constructed to vaporize said liquid conductor and ,discharge itinto said container under the influence of excess current, saidcontainer being substantially sealed to confine any dlscharged vaportherewithin where it contacts with said electrodes and other metallic iparts, said metallic jacket being insulated from said metallic feed tubeand from both electrodes to minimize the chance of arcing between saidjacket and said second electrode, and being flanged inwardly at one endaround an enlarged terminal of said feed tube and being flanged inwardlyat its other end around a shoulder of said control tube.

STANLEY s. GEEN.

